1. Field of the Invention
The present invention relates generally to loop facilities management in a telephone company network. More specifically, the present invention relates to improving the automated loop makeup process.
2. Background of the Invention
Information regarding the physical layout of telephone network facilities is generally stored in two basic systems—a facilities database system and an assignment database system. The facilities database system stores the information in plats in one of two forms—a paper form and a mechanized form (described later). Traditionally, plats were paper records or a series of paper records which show the telephone systems network facilities superimposed on a land base map that shows features of the land. These land features include, for example, roads, streets, and major geological features such as rivers and lakes. Thus, the plats provide a graphical view of the relationship of the telephone system network's facilities to the land features. For example, a plat can show that a telephone cable is routed up north along Main Street on the west side of the road and then that the cable is routed west along First Street.
Information about the telephone facilities described on a plat is also typically included on the plat. For example, information such as a facility's type, year it was placed into use and its size can be provided on the plat. Where a telephone system facility is a cable, for example, its size in terms of the number of copper wire pairs it contains, as well as their length and gauge are typically included on the plat. Other facility types include poles, conduits, terminals and other telephone network equipment. Other information can also be provided on the plat depending on the facility type. Continuing the example where the facility is a cable, the plat can also provide information as to whether the cable is buried, run through a conduit underground, attached to poles or run from building to building.
FIG. 1 is an exemplary plat 101 (without land base underlay) that illustrates the kind of information and nomenclature typically found in plats describing telephone facilities. A central office 102 is shown having a cable 104 connected to a feeder distribution interface (FDI) 106. As shown in exemplary plat 101, cable 104 is buried, 500 feet long and comprises 100 26-gauge copper wire pairs. Cable 104 is assigned 1 as its cable identifier. Collectively, the copper wire pairs contained in cable 104 are identified by the pair range 1–100 with 4 complements (typically 25 pairs @), 1–25, 26–50, 51–75, 76–100.
FDI 106 serves as a cross connect point or cross box. In essence, FDI 106 provides a mechanism for connecting facilities feeder to distribution without requiring separate splicing. Plat 101 provides descriptive information for FDI 106. As shown in plat 101, the address of FDI 106 is 100 Main Street. In addition, plat 101 shows that FDI 106 has capacity for 300 input cable pairs. The feeder cable and cable pairs are identified by the cable:pair range 1:1–300. However, as shown in plat 101, only 100 cable pairs (pairs 1–100) are currently connected (spliced) to FDI 106. The remaining capacity for 200 feeder cable pairs (identified as dd:101–300) is unused. FDI 106 outputs cable pairs 1–600 identified with a cable ID of 101. The feeder/distribution characteristics of FDI 106 can be described as in count of cable 1, pairs 1 through 100 and an out count of cable 101, pairs 1 to 600.
FDI 106 has a distribution cable 108. Distribution cable 108 is characterized on plat 101 as a buried 800-foot copper cable containing 200 26-gauge copper wire pairs. Cable 108 is assigned the cable identifier 101, and the 200 copper wire pairs are identified by the cable:pair range 101:1–200.
Cable 108 is spliced into a cable 110 at a splice 109. Cable 110 is described on plat 101 as a buried 700-foot copper cable containing a 25 24-gauge copper wire pairs. Cable 110 is identified by the cable identifier 101 and the 25 pairs are identified by the pair range 101:1–25.
Cable 110 is coupled to a terminal 112. As shown in plat 101, terminal 112 is a distribution terminal. A distribution terminal is a service provisioning access point. Typically, a distribution terminal has an in count, but no out count. As shown in plat 101, terminal 112 has an input for the 25 copper wires contained in cable 110 identified as 101:101–125.
A second form of plats is known as mechanized plats. Mechanized plats have been used to store information about telephone network facilities in the facilities database. A mechanized plat is an intelligent graphic, in which the physical facilities shown in the plat are linked to a database that contains information about the facilities rather than simply being scanned and stored. Exemplary facilities databases that can store mechanized plats include PLRMS from Intergraph of Huntsville, Ala.; EWO from Byers Engineering of Atlanta, Ga.; and Network Engineer from Mesa Solutions of Huntsville, Ala. Mechanized plats provide significantly greater flexibility than paper plats or simple scanned plats. For example, mechanized plats provide the ability to perform automatic traces on a given pair range.
The second basic system for storing telephone system network information is an assignment system. An exemplary assignment system is the Loop Facility Assignment and Control System (LFACS) produced and supported by Telcordia. LFACS is a circuit provisioning or assignment database application that is used by most of the Regional Bell Operating Companies (RBOCS).
LFACS models the telecommunications network as a series of cable-pairs and terminals. A cable-pair originates at either a central office feeder or an FDI x-BOX (Distribution). LFACS determines circuit assignments to provide service to customers. Based on “will serve” information, each circuit assignment is identified by a circuit identifier (CKID) and associated with a customer telephone number. Storage of LFACS circuit assignments is described with respect to FIG. 2.
FIG. 2 is a schematic illustration of facilities information corresponding to FIG. 1. LFACS first identifies the terminal which serves the customer's address, (will serve) such as terminal 210 in FIG. 2. LFACS then attempts to find cable pairs from terminal 210 back to the central office which are compatible with the customer's service. The set of cable pairs so determined are the circuit assignments for providing the customer service to the customers.
The assignments are made according to a set of rules. For example, one rule is that only cable pairs compatible with the service to be provided to the customer can be used. For example, a cable pair that is provisioned for T-1 data service will not be assigned to provide plain old telephone service. Another rule that LFACS follows in making circuit assignments is whether a proposed assignment has capacity to handle the service that the customer desires. For example, if a customer desires ADSL service, LFACS can look at loss calculations or an ADSL “flag” to ensure that the proposed assignment can support the ADSL service. Another consideration that is used is the length of the proposed circuit. For example, the maximum length from a central office for ADSL service is 18,000 feet. Thus, the proposed assignment for ADSL service must be within this distance from the central office. The gauge of the wire is also a consideration in loss calculations for making circuit assignments. For example, lower gauge wire can be used to carry higher capacity data over longer distances.
If LFACS finds a compatible cable pair that can provide the service to the customer, LFACS follows the cable pair to the terminal where that cable pair originates. For example, referring to FIG. 2, if LFACS determines that a cable pair in cable:pair range 101:101–125 feeding terminal 210 can provide the service, LFACS follows the cable pair to where it originates. In this case the cable pair originates at FDI 206 through cable 208. LFACS then searches for compatible cable pairs which originate in the central office 202 through cable 204 that can be cross-connected through FDI 206 to the cable pair in cable:pair range 101:101–125 that was identified by LFACS. For example, assuming compatibility exists, a customer desiring POTS service might be assigned cable 101, pair 107 at FDI 206, and then cross-connected to cable 1, pair 1 at central office 202. This circuit is assigned a circuit ID such as a telephone number, for example, (555) 123-4567.
To ensure compatibility when it is generating circuit assignments to provide customer service, LFACS stores facility information for each terminal facility in the telephone network. This information, for example, includes length and gauge information for each wire pair or group of wire pairs that are distributed from a terminal in the telephone network. For example, for terminal 206, cable 1 pairs 1 through 100, LFACS can store information for that entire pair range or for subsets of that pair range, depending on how they are routed through the network.
As shown in FIG. 1, cable 1, pairs 1 through 100 all take the same path. Thus, LFACS stores 800 feet of 26-gauge cable for this pair range. If one or more of those cable pairs had divergent paths at some point, and then come back together at terminal 206, LFACS can store that information as well. For example, cable pairs 1 to 50 may have been that 800 feet of 26-gauge wire cable pairs and cable pairs 51 to 100 may have been 400 feet of 26-gauge wire cable pairs with an additional 200 feet of 24-gauge wire.
It can be seen that the facilities database system stores data that can be used to determine various criteria. For example, the length and gauge information stored in the facilities database can be used to determine loss characteristics of a potential circuit. The assignment database (e.g., LFACS) stores the relationship between a circuit and its different components.
A relationship was built into LFACS to store length and gauge information corresponding to the wire pairs it stores. This relationship is called a terminal make-up (TMU). Referring to FIGS. 1 and 2, for example, the TMU for terminal 210 is 800 feet of 26-gauge copper wire followed by 700 feet of 24-gauge copper wire. The TMU for terminal 206 is 500 feet of 26-gauge copper wire.
A loop make-up is the combination of the TMUs for a particular circuit. For example, for the circuit assigned to telephone number (555) 123-4567 described above, the LMU is 26:500 x 26:800, 24:700 (where “x” indicates a cross point from central office 202 to FDI 206.
Historically, TMU data was entered into LFACS manually. This process is time consuming and prone to error. The use of mechanized plats allowed this process to be automated using an extract from LFACS. An extract is a text file that is generated from LFACS for a particular wire center. The extract lists some or all of the terminals that exist in LFACS. The basic properties of the extract text file include the terminal name and the complements which are associated with that terminal.
An extract is taken from LFACS and input to a computer application. The computer application runs the loop make-up process for every terminal in that extract and then automatically stores the loop make-up information into LFACS.
FIG. 3 is a flow chart illustrating the automatic process for generating and storing LMUs using LFACS extracts. In step 302, a terminal name is retrieved from the LFACS extract, along with its associated complements. As used herein, a complement refers to a pair range, i.e., a range of cable wire pairs. LFACS searches the mechanized plats (stored in the facilities database) for a matching terminal name in step 304. If there is no terminal name match (as determined in step 306), the system generates an error in step 312. If the terminal name does exist, then the system continues in step 308 by determining whether the complement associated with the terminal exists in the facilities database. If the complement does not exist, an error is generated in step 312. If the complement does exist, the system attempts to run LMU to perform the assignment in step 310. In step 314, the system determines whether the LMU operation completed successfully. If the operation completes successfully, the resulting loop make up is entered into LFACS in step 316. Otherwise, an error is generated in step 312.
Thus, this process is dependent upon matching terminal names. There is a fundamental problem with this dependency. That problem is that there is no tool that enforces data integrity between the assignment and facilities databases. For example, approximately 70–80% of the errors reported by step 312 result because no matching terminal is found in the facilities database in step 306. This is true even where “fuzzy” logic is used to try to make the match, in which names do not have to match exactly.